campaign trail. Turbo charged now, that mitt romney picked running mate paul ryan. The 42-year-old congressman is married. He has three kids. Also a fitness fin natuanatic. There you see him with tony horton. We have the election team with jon karl, jake tapper. David muir has all of the details from st. Agustin, florida. Turbo charged that perfect world. Headlines this morning, bold choice. Others say romney rolling the dice. If this campaign was looking for a brand-new burst of energy that's what they got as they carved out new battleground lines in the race for president. Paul ryan choking up greeted by a crowd of 10,000 strong in the home state of wisconsin. It's good to be home. Reporter: Ryan is known in the political world for the controversial budget plan that calls for steep cuts and the obama campaign said it would change medicare as we know it. Mitt romney and his running mate seemed ready for the incoming fire on "60 minutes." There's only one president that robbed medicare $716 billion to pay for new risky program of his own that we call obama care. Ryan pointing out his own mother is on medicare in florida. Our point, we need to preserve their benefits. Reporter: Romney said it's two on two. And ryan is wasting no time taking on the president. They are not working. They are failing us. They can't run on that. They are making hope and change to attack and blame. Reporter: When asked about releasing only two years of his tax return, ryan shifting again to the president. What I hear from people around this country, they are not asking where are the tax returns, they are asking where the jobs are. Reporter: And the first time, president obama weighing in on the republican ticket. I want to congratulate congressman ryan. The president calling him decent, a family man. Then he started winging. He's an articulate spokesman for governor romney's plan. They tried to sell us this trickle down fairy dust before and guess what? It did not work. Reporter: What did work was the romney campaign plan to deep the vp choice a secret. As speculation grew he would be romney's choice, he was dropped off at home by an aide on the eve of the big announcement. Ryan telling us he lost his trees but we know he made a mad dash behind the woods, the same woods he played in as a child. An aide waiting for him. I know the woods like the back of my hand. Reporter: Waiting for paul ryan in that truck, they drove him to illinois. He flew to north carolina, members of the romney team waiting for him there. They had takeout from applebe applebee's. Who knew we should have staked out applebee's. He got one on you. Thanks so much.

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